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Data Structures | Macros | Typedefs | Enumerations | Functions
control.h File Reference

Application interface library for the ALSA driver. More...

Go to the source code of this file.

## Data Structures
struct | snd_aes_iec958_t

## Macros
#define | __ALSA_CONTROL_H
#define | SND_CONTROL_DLSYM_VERSION _dlsym_control_001
#define | SND_CTL_EVENT_MASK_REMOVE
#define | SND_CTL_EVENT_MASK_VALUE
#define | SND_CTL_EVENT_MASK_INFO
#define | SND_CTL_EVENT_MASK_ADD
#define | SND_CTL_EVENT_MASK_TLV
#define | SND_CTL_NAME_NONE ""
#define | SND_CTL_NAME_PLAYBACK "Playback "
#define | SND_CTL_NAME_CAPTURE "Capture "
#define | SND_CTL_NAME_IEC958_NONE ""
#define | SND_CTL_NAME_IEC958_SWITCH "Switch"
#define | SND_CTL_NAME_IEC958_VOLUME "Volume"
#define | SND_CTL_NAME_IEC958_DEFAULT "Default"
#define | SND_CTL_NAME_IEC958_MASK "Mask"
#define | SND_CTL_NAME_IEC958_CON_MASK "Con Mask"
#define | SND_CTL_NAME_IEC958_PRO_MASK "Pro Mask"
#define | SND_CTL_NAME_IEC958_PCM_STREAM "PCM Stream"
#define | SND_CTL_NAME_IEC958(expl, direction, what)
#define | SND_CTL_POWER_MASK 0xff00
#define | SND_CTL_POWER_D0 0x0000
#define | SND_CTL_POWER_D1 0x0100
#define | SND_CTL_POWER_D2 0x0200
#define | SND_CTL_POWER_D3 0x0300
#define | SND_CTL_POWER_D3hot (SND_CTL_POWER_D3|0x0000)
#define | SND_CTL_POWER_D3cold (SND_CTL_POWER_D3|0x0001)
#define | SND_CTL_TLVT_CONTAINER 0x0000
#define | SND_CTL_TLVT_DB_SCALE 0x0001
#define | SND_CTL_TLVT_DB_LINEAR 0x0002
#define | SND_CTL_TLVT_DB_RANGE 0x0003
#define | SND_CTL_TLVT_DB_MINMAX 0x0004
#define | SND_CTL_TLVT_DB_MINMAX_MUTE 0x0005
#define | SND_CTL_TLV_DB_GAIN_MUTE -9999999
#define | SND_CTL_TLVT_CHMAP_FIXED 0x00101
#define | SND_CTL_TLVT_CHMAP_VAR 0x00102
#define | SND_CTL_TLVT_CHMAP_PAIRED 0x00103
#define | SND_CTL_NONBLOCK
#define | SND_CTL_ASYNC
#define | SND_CTL_READONLY
#define | SND_CTL_EINTR
#define | SND_SCTL_NOFREE 0x0001
#define | snd_ctl_elem_id_alloca(ptr)
| allocate an invalid snd_ctl_elem_id_t using standard alloca
#define | snd_ctl_card_info_alloca(ptr)
| Allocate an invalid snd_ctl_card_info_t on the stack.
#define | snd_ctl_event_alloca(ptr)
| allocate an invalid snd_ctl_event_t using standard alloca
#define | snd_ctl_elem_list_alloca(ptr)
| Allocate a snd_ctl_elem_list_t using standard alloca.
#define | snd_ctl_elem_info_alloca(ptr)
| allocate an invalid snd_ctl_elem_info_t using standard alloca
#define | snd_ctl_elem_value_alloca(ptr)
| Allocate an invalid snd_ctl_elem_value_t on the stack.

## Typedefs
typedef struct _snd_ctl_card_info | snd_ctl_card_info_t
| CTL card info container.
typedef struct _snd_ctl_elem_id | snd_ctl_elem_id_t
typedef struct _snd_ctl_elem_list | snd_ctl_elem_list_t
typedef struct _snd_ctl_elem_info | snd_ctl_elem_info_t
typedef struct _snd_ctl_elem_value | snd_ctl_elem_value_t
typedef struct _snd_ctl_event | snd_ctl_event_t
typedef struct _snd_ctl | snd_ctl_t
typedef struct _snd_sctl | snd_sctl_t
typedef struct _snd_hctl_elem | snd_hctl_elem_t
typedef struct _snd_hctl | snd_hctl_t
typedef int(* | snd_hctl_compare_t) (const snd_hctl_elem_t *e1, const snd_hctl_elem_t *e2)
| Compare function for sorting HCTL elements.
typedef int(* | snd_hctl_callback_t) (snd_hctl_t *hctl, unsigned int mask, snd_hctl_elem_t *elem)
| HCTL callback function.
typedef int(* | snd_hctl_elem_callback_t) (snd_hctl_elem_t *elem, unsigned int mask)
| HCTL element callback function.

## Enumerations
enum | snd_ctl_elem_type_t { SND_CTL_ELEM_TYPE_NONE = 0 , SND_CTL_ELEM_TYPE_BOOLEAN , SND_CTL_ELEM_TYPE_INTEGER , SND_CTL_ELEM_TYPE_ENUMERATED , SND_CTL_ELEM_TYPE_BYTES , SND_CTL_ELEM_TYPE_IEC958 , SND_CTL_ELEM_TYPE_INTEGER64 , SND_CTL_ELEM_TYPE_LAST = SND_CTL_ELEM_TYPE_INTEGER64 }
enum | snd_ctl_elem_iface_t { SND_CTL_ELEM_IFACE_CARD = 0 , SND_CTL_ELEM_IFACE_HWDEP , SND_CTL_ELEM_IFACE_MIXER , SND_CTL_ELEM_IFACE_PCM , SND_CTL_ELEM_IFACE_RAWMIDI , SND_CTL_ELEM_IFACE_TIMER , SND_CTL_ELEM_IFACE_SEQUENCER , SND_CTL_ELEM_IFACE_LAST = SND_CTL_ELEM_IFACE_SEQUENCER }
enum | snd_ctl_event_type_t { SND_CTL_EVENT_ELEM = 0 , SND_CTL_EVENT_LAST = SND_CTL_EVENT_ELEM }
enum | snd_ctl_type_t { SND_CTL_TYPE_HW , SND_CTL_TYPE_SHM , SND_CTL_TYPE_INET , SND_CTL_TYPE_EXT , SND_CTL_TYPE_REMAP }

## Functions
int | snd_card_load (int card)
| Try to load the driver for a card.
int | snd_card_next (int *card)
| Iterate over physical sound cards.
int | snd_card_get_index (const char *name)
| Convert a card string to the card index.
int | snd_card_get_name (int card, char **name)
| Obtain the card name.
int | snd_card_get_longname (int card, char **name)
| Obtain the card long name.
int | snd_ctl_open (snd_ctl_t **ctl, const char *name, int mode)
| Opens a sound card.
int | snd_ctl_open_lconf (snd_ctl_t **ctl, const char *name, int mode, snd_config_t *lconf)
| Opens a CTL using local configuration.
int | snd_ctl_open_fallback (snd_ctl_t **ctl, snd_config_t *root, const char *name, const char *orig_name, int mode)
| Opens a fallback CTL.
int | snd_ctl_close (snd_ctl_t *ctl)
| close CTL handle
int | snd_ctl_nonblock (snd_ctl_t *ctl, int nonblock)
| set nonblock mode
int | snd_async_add_ctl_handler (snd_async_handler_t **handler, snd_ctl_t *ctl, snd_async_callback_t callback, void *private_data)
| Add an async handler for a CTL.
snd_ctl_t * | snd_async_handler_get_ctl (snd_async_handler_t *handler)
| Return CTL handle related to an async handler.
int | snd_ctl_poll_descriptors_count (snd_ctl_t *ctl)
| get count of poll descriptors for CTL handle
int | snd_ctl_poll_descriptors (snd_ctl_t *ctl, struct pollfd *pfds, unsigned int space)
| get poll descriptors
int | snd_ctl_poll_descriptors_revents (snd_ctl_t *ctl, struct pollfd *pfds, unsigned int nfds, unsigned short *revents)
| get returned events from poll descriptors
int | snd_ctl_subscribe_events (snd_ctl_t *ctl, int subscribe)
| Ask to be informed about events (poll, snd_async_add_ctl_handler, snd_ctl_read)
int | snd_ctl_card_info (snd_ctl_t *ctl, snd_ctl_card_info_t *info)
| Get information about the sound card.
int | snd_ctl_elem_list (snd_ctl_t *ctl, snd_ctl_elem_list_t *list)
| Get a list of element identifiers.
int | snd_ctl_elem_info (snd_ctl_t *ctl, snd_ctl_elem_info_t *info)
| Get CTL element information.
int | snd_ctl_elem_read (snd_ctl_t *ctl, snd_ctl_elem_value_t *data)
| Get CTL element value.
int | snd_ctl_elem_write (snd_ctl_t *ctl, snd_ctl_elem_value_t *data)
| Set CTL element value.
int | snd_ctl_elem_lock (snd_ctl_t *ctl, snd_ctl_elem_id_t *id)
| Lock CTL element.
int | snd_ctl_elem_unlock (snd_ctl_t *ctl, snd_ctl_elem_id_t *id)
| Unlock CTL element.
int | snd_ctl_elem_tlv_read (snd_ctl_t *ctl, const snd_ctl_elem_id_t *id, unsigned int *tlv, unsigned int tlv_size)
| Read structured data from an element set to given buffer.
int | snd_ctl_elem_tlv_write (snd_ctl_t *ctl, const snd_ctl_elem_id_t *id, const unsigned int *tlv)
| Write structured data from given buffer to an element set.
int | snd_ctl_elem_tlv_command (snd_ctl_t *ctl, const snd_ctl_elem_id_t *id, const unsigned int *tlv)
| Process structured data from given buffer for an element set.
int | snd_ctl_set_power_state (snd_ctl_t *ctl, unsigned int state)
| Set Power State to given SND_CTL_POWER_* value and do the power management.
int | snd_ctl_get_power_state (snd_ctl_t *ctl, unsigned int *state)
| Get actual Power State.
int | snd_ctl_read (snd_ctl_t *ctl, snd_ctl_event_t *event)
| Read an event.
int | snd_ctl_wait (snd_ctl_t *ctl, int timeout)
| Wait for a CTL to become ready (i.e. at least one event pending)
const char * | snd_ctl_name (snd_ctl_t *ctl)
| get identifier of CTL handle
snd_ctl_type_t | snd_ctl_type (snd_ctl_t *ctl)
| get type of CTL handle
const char * | snd_ctl_elem_type_name (snd_ctl_elem_type_t type)
| get name of a CTL element type
const char * | snd_ctl_elem_iface_name (snd_ctl_elem_iface_t iface)
| get name of a CTL element related interface
const char * | snd_ctl_event_type_name (snd_ctl_event_type_t type)
| get name of a CTL event type
unsigned int | snd_ctl_event_elem_get_mask (const snd_ctl_event_t *obj)
| Get event mask for an element related event.
unsigned int | snd_ctl_event_elem_get_numid (const snd_ctl_event_t *obj)
| Get element numeric identifier for an element related event.
void | snd_ctl_event_elem_get_id (const snd_ctl_event_t *obj, snd_ctl_elem_id_t *ptr)
| Get CTL element identifier for an element related event.
snd_ctl_elem_iface_t | snd_ctl_event_elem_get_interface (const snd_ctl_event_t *obj)
| Get interface part of CTL element identifier for an element related event.
unsigned int | snd_ctl_event_elem_get_device (const snd_ctl_event_t *obj)
| Get device part of CTL element identifier for an element related event.
unsigned int | snd_ctl_event_elem_get_subdevice (const snd_ctl_event_t *obj)
| Get subdevice part of CTL element identifier for an element related event.
const char * | snd_ctl_event_elem_get_name (const snd_ctl_event_t *obj)
| Get name part of CTL element identifier for an element related event.
unsigned int | snd_ctl_event_elem_get_index (const snd_ctl_event_t *obj)
| Get index part of CTL element identifier for an element related event.
int | snd_ctl_elem_list_alloc_space (snd_ctl_elem_list_t *obj, unsigned int entries)
| allocate space for CTL element identifiers list
void | snd_ctl_elem_list_free_space (snd_ctl_elem_list_t *obj)
| free previously allocated space for CTL element identifiers list
char * | snd_ctl_ascii_elem_id_get (snd_ctl_elem_id_t *id)
| return ASCII CTL element identifier name
int | snd_ctl_ascii_elem_id_parse (snd_ctl_elem_id_t *dst, const char *str)
| parse ASCII string as CTL element identifier
int | snd_ctl_ascii_value_parse (snd_ctl_t *handle, snd_ctl_elem_value_t *dst, snd_ctl_elem_info_t *info, const char *value)
| parse ASCII string as CTL element value
size_t | snd_ctl_elem_id_sizeof (void)
| get size of snd_ctl_elem_id_t
int | snd_ctl_elem_id_malloc (snd_ctl_elem_id_t **ptr)
| allocate an invalid snd_ctl_elem_id_t using standard malloc
void | snd_ctl_elem_id_free (snd_ctl_elem_id_t *obj)
| frees a previously allocated snd_ctl_elem_id_t
void | snd_ctl_elem_id_clear (snd_ctl_elem_id_t *obj)
| clear given snd_ctl_elem_id_t object
void | snd_ctl_elem_id_copy (snd_ctl_elem_id_t *dst, const snd_ctl_elem_id_t *src)
| copy one snd_ctl_elem_id_t to another
int | snd_ctl_elem_id_compare_numid (const snd_ctl_elem_id_t *id1, const snd_ctl_elem_id_t *id2)
| compare one snd_ctl_elem_id_t to another using numid
int | snd_ctl_elem_id_compare_set (const snd_ctl_elem_id_t *id1, const snd_ctl_elem_id_t *id2)
| compare one snd_ctl_elem_id_t to another
unsigned int | snd_ctl_elem_id_get_numid (const snd_ctl_elem_id_t *obj)
| Get numeric identifier from a CTL element identifier.
snd_ctl_elem_iface_t | snd_ctl_elem_id_get_interface (const snd_ctl_elem_id_t *obj)
| Get interface part of a CTL element identifier.
unsigned int | snd_ctl_elem_id_get_device (const snd_ctl_elem_id_t *obj)
| Get device part of a CTL element identifier.
unsigned int | snd_ctl_elem_id_get_subdevice (const snd_ctl_elem_id_t *obj)
| Get subdevice part of a CTL element identifier.
const char * | snd_ctl_elem_id_get_name (const snd_ctl_elem_id_t *obj)
| Get name part of a CTL element identifier.
unsigned int | snd_ctl_elem_id_get_index (const snd_ctl_elem_id_t *obj)
| Get index part of a CTL element identifier.
void | snd_ctl_elem_id_set_numid (snd_ctl_elem_id_t *obj, unsigned int val)
| Set numeric identifier for a CTL element identifier.
void | snd_ctl_elem_id_set_interface (snd_ctl_elem_id_t *obj, snd_ctl_elem_iface_t val)
| Set interface part for a CTL element identifier.
void | snd_ctl_elem_id_set_device (snd_ctl_elem_id_t *obj, unsigned int val)
| Set device part for a CTL element identifier.
void | snd_ctl_elem_id_set_subdevice (snd_ctl_elem_id_t *obj, unsigned int val)
| Set subdevice part for a CTL element identifier.
void | snd_ctl_elem_id_set_name (snd_ctl_elem_id_t *obj, const char *val)
| Set name part for a CTL element identifier.
void | snd_ctl_elem_id_set_index (snd_ctl_elem_id_t *obj, unsigned int val)
| Set index part for a CTL element identifier.
size_t | snd_ctl_card_info_sizeof (void)
| get size of snd_ctl_card_info_t.
int | snd_ctl_card_info_malloc (snd_ctl_card_info_t **ptr)
| Allocate an invalid snd_ctl_card_info_t on the heap.
void | snd_ctl_card_info_free (snd_ctl_card_info_t *obj)
| Free an snd_ctl_card_info_t previously allocated using snd_ctl_card_info_malloc().
void | snd_ctl_card_info_clear (snd_ctl_card_info_t *obj)
| Clear given card info object.
void | snd_ctl_card_info_copy (snd_ctl_card_info_t *dst, const snd_ctl_card_info_t *src)
| Bitwise copy of a snd_ctl_card_info_t object.
int | snd_ctl_card_info_get_card (const snd_ctl_card_info_t *obj)
| Get the sound card index from the given info object.
const char * | snd_ctl_card_info_get_id (const snd_ctl_card_info_t *obj)
| Get the sound card ID from the given info object.
const char * | snd_ctl_card_info_get_driver (const snd_ctl_card_info_t *obj)
| Get the sound card driver from the given info object.
const char * | snd_ctl_card_info_get_name (const snd_ctl_card_info_t *obj)
| Get the sound card name from the given info object.
const char * | snd_ctl_card_info_get_longname (const snd_ctl_card_info_t *obj)
| Get the sound cards long name from the given info object.
const char * | snd_ctl_card_info_get_mixername (const snd_ctl_card_info_t *obj)
| Get the sound card mixer name from the given info object.
const char * | snd_ctl_card_info_get_components (const snd_ctl_card_info_t *obj)
| Get the sound cards "components" property from the given info object.
size_t | snd_ctl_event_sizeof (void)
| get size of snd_ctl_event_t
int | snd_ctl_event_malloc (snd_ctl_event_t **ptr)
| allocate an invalid snd_ctl_event_t using standard malloc
void | snd_ctl_event_free (snd_ctl_event_t *obj)
| frees a previously allocated snd_ctl_event_t
void | snd_ctl_event_clear (snd_ctl_event_t *obj)
| clear given snd_ctl_event_t object
void | snd_ctl_event_copy (snd_ctl_event_t *dst, const snd_ctl_event_t *src)
| copy one snd_ctl_event_t to another
snd_ctl_event_type_t | snd_ctl_event_get_type (const snd_ctl_event_t *obj)
| Get type of a CTL event.
size_t | snd_ctl_elem_list_sizeof (void)
| get size of snd_ctl_elem_list_t.
int | snd_ctl_elem_list_malloc (snd_ctl_elem_list_t **ptr)
| allocate a snd_ctl_elem_list_t using standard malloc.
void | snd_ctl_elem_list_free (snd_ctl_elem_list_t *obj)
| frees a previously allocated snd_ctl_elem_list_t.
void | snd_ctl_elem_list_clear (snd_ctl_elem_list_t *obj)
| Clear given snd_ctl_elem_list_t object.
void | snd_ctl_elem_list_copy (snd_ctl_elem_list_t *dst, const snd_ctl_elem_list_t *src)
| copy one snd_ctl_elem_list_t to another.
void | snd_ctl_elem_list_set_offset (snd_ctl_elem_list_t *obj, unsigned int val)
| Set index of first wanted CTL element identifier in a CTL element identifiers list.
unsigned int | snd_ctl_elem_list_get_used (const snd_ctl_elem_list_t *obj)
| Get number of used entries in CTL element identifiers list.
unsigned int | snd_ctl_elem_list_get_count (const snd_ctl_elem_list_t *obj)
| Get total count of elements present in CTL device.
void | snd_ctl_elem_list_get_id (const snd_ctl_elem_list_t *obj, unsigned int idx, snd_ctl_elem_id_t *ptr)
| Get CTL element identifier for an entry of a CTL element identifiers list.
unsigned int | snd_ctl_elem_list_get_numid (const snd_ctl_elem_list_t *obj, unsigned int idx)
| Get CTL element numeric identifier for an entry of a CTL element identifiers list.
snd_ctl_elem_iface_t | snd_ctl_elem_list_get_interface (const snd_ctl_elem_list_t *obj, unsigned int idx)
| Get interface part of CTL element identifier for an entry of a CTL element identifiers list.
unsigned int | snd_ctl_elem_list_get_device (const snd_ctl_elem_list_t *obj, unsigned int idx)
| Get the device part of CTL element identifier for an entry of a CTL element identifiers list.
unsigned int | snd_ctl_elem_list_get_subdevice (const snd_ctl_elem_list_t *obj, unsigned int idx)
| Get subdevice part of CTL element identifier for an entry of a CTL element identifiers list.
const char * | snd_ctl_elem_list_get_name (const snd_ctl_elem_list_t *obj, unsigned int idx)
| Get name part of CTL element identifier for an entry of a CTL element identifiers list.
unsigned int | snd_ctl_elem_list_get_index (const snd_ctl_elem_list_t *obj, unsigned int idx)
| Get index part of CTL element identifier for an entry of a CTL element identifiers list.
size_t | snd_ctl_elem_info_sizeof (void)
| get size of snd_ctl_elem_info_t
int | snd_ctl_elem_info_malloc (snd_ctl_elem_info_t **ptr)
| allocate an invalid snd_ctl_elem_info_t using standard malloc
void | snd_ctl_elem_info_free (snd_ctl_elem_info_t *obj)
| frees a previously allocated snd_ctl_elem_info_t
void | snd_ctl_elem_info_clear (snd_ctl_elem_info_t *obj)
| clear given snd_ctl_elem_info_t object
void | snd_ctl_elem_info_copy (snd_ctl_elem_info_t *dst, const snd_ctl_elem_info_t *src)
| copy one snd_ctl_elem_info_t to another
snd_ctl_elem_type_t | snd_ctl_elem_info_get_type (const snd_ctl_elem_info_t *obj)
| Get type from a CTL element id/info.
int | snd_ctl_elem_info_is_readable (const snd_ctl_elem_info_t *obj)
| Get info about readability from a CTL element id/info.
int | snd_ctl_elem_info_is_writable (const snd_ctl_elem_info_t *obj)
| Get info about writability from a CTL element id/info.
int | snd_ctl_elem_info_is_volatile (const snd_ctl_elem_info_t *obj)
| Get info about notification feasibility from a CTL element id/info.
int | snd_ctl_elem_info_is_inactive (const snd_ctl_elem_info_t *obj)
| Get info about status from a CTL element id/info.
int | snd_ctl_elem_info_is_locked (const snd_ctl_elem_info_t *obj)
| Get info whether an element is locked.
int | snd_ctl_elem_info_is_tlv_readable (const snd_ctl_elem_info_t *obj)
| Get info about TLV readability from a CTL element id/info.
int | snd_ctl_elem_info_is_tlv_writable (const snd_ctl_elem_info_t *obj)
| Get info about TLV writeability from a CTL element id/info.
int | snd_ctl_elem_info_is_tlv_commandable (const snd_ctl_elem_info_t *obj)
| Get info about TLV command possibility from a CTL element id/info.
int | snd_ctl_elem_info_is_owner (const snd_ctl_elem_info_t *obj)
| Get info if I own an element.
int | snd_ctl_elem_info_is_user (const snd_ctl_elem_info_t *obj)
| Get info if it's a user element.
pid_t | snd_ctl_elem_info_get_owner (const snd_ctl_elem_info_t *obj)
| Get owner of a locked element.
unsigned int | snd_ctl_elem_info_get_count (const snd_ctl_elem_info_t *obj)
| Get number of value entries from a CTL element id/info.
long | snd_ctl_elem_info_get_min (const snd_ctl_elem_info_t *obj)
| Get minimum value from a SND_CTL_ELEM_TYPE_INTEGER CTL element id/info.
long | snd_ctl_elem_info_get_max (const snd_ctl_elem_info_t *obj)
| Get maximum value from a SND_CTL_ELEM_TYPE_INTEGER CTL element id/info.
long | snd_ctl_elem_info_get_step (const snd_ctl_elem_info_t *obj)
| Get value step from a SND_CTL_ELEM_TYPE_INTEGER CTL element id/info.
long long | snd_ctl_elem_info_get_min64 (const snd_ctl_elem_info_t *obj)
| Get minimum value from a SND_CTL_ELEM_TYPE_INTEGER64 CTL element id/info.
long long | snd_ctl_elem_info_get_max64 (const snd_ctl_elem_info_t *obj)
| Get maximum value from a SND_CTL_ELEM_TYPE_INTEGER64 CTL element id/info.
long long | snd_ctl_elem_info_get_step64 (const snd_ctl_elem_info_t *obj)
| Get value step from a SND_CTL_ELEM_TYPE_INTEGER64 CTL element id/info.
unsigned int | snd_ctl_elem_info_get_items (const snd_ctl_elem_info_t *obj)
| Get number of items available from a SND_CTL_ELEM_TYPE_ENUMERATED CTL element id/info.
void | snd_ctl_elem_info_set_item (snd_ctl_elem_info_t *obj, unsigned int val)
| Select item in a SND_CTL_ELEM_TYPE_ENUMERATED CTL element id/info.
const char * | snd_ctl_elem_info_get_item_name (const snd_ctl_elem_info_t *obj)
| Get name for selected item in a SND_CTL_ELEM_TYPE_ENUMERATED CTL element id/info.
int | snd_ctl_elem_info_get_dimensions (const snd_ctl_elem_info_t *obj)
| Get count of dimensions for given element.
int | snd_ctl_elem_info_get_dimension (const snd_ctl_elem_info_t *obj, unsigned int idx)
| Get specified of dimension width for given element.
int | snd_ctl_elem_info_set_dimension (snd_ctl_elem_info_t *info, const int dimension[4])
| Set width to a specified dimension level of given element information.
void | snd_ctl_elem_info_get_id (const snd_ctl_elem_info_t *obj, snd_ctl_elem_id_t *ptr)
| Get CTL element identifier of a CTL element id/info.
unsigned int | snd_ctl_elem_info_get_numid (const snd_ctl_elem_info_t *obj)
| Get element numeric identifier of a CTL element id/info.
snd_ctl_elem_iface_t | snd_ctl_elem_info_get_interface (const snd_ctl_elem_info_t *obj)
| Get interface part of CTL element identifier of a CTL element id/info.
unsigned int | snd_ctl_elem_info_get_device (const snd_ctl_elem_info_t *obj)
| Get device part of CTL element identifier of a CTL element id/info.
unsigned int | snd_ctl_elem_info_get_subdevice (const snd_ctl_elem_info_t *obj)
| Get subdevice part of CTL element identifier of a CTL element id/info.
const char * | snd_ctl_elem_info_get_name (const snd_ctl_elem_info_t *obj)
| Get name part of CTL element identifier of a CTL element id/info.
unsigned int | snd_ctl_elem_info_get_index (const snd_ctl_elem_info_t *obj)
| Get index part of CTL element identifier of a CTL element id/info.
void | snd_ctl_elem_info_set_id (snd_ctl_elem_info_t *obj, const snd_ctl_elem_id_t *ptr)
| Set CTL element identifier of a CTL element id/info.
void | snd_ctl_elem_info_set_numid (snd_ctl_elem_info_t *obj, unsigned int val)
| Set element numeric identifier of a CTL element id/info.
void | snd_ctl_elem_info_set_interface (snd_ctl_elem_info_t *obj, snd_ctl_elem_iface_t val)
| Set interface part of CTL element identifier of a CTL element id/info.
void | snd_ctl_elem_info_set_device (snd_ctl_elem_info_t *obj, unsigned int val)
| Set device part of CTL element identifier of a CTL element id/info.
void | snd_ctl_elem_info_set_subdevice (snd_ctl_elem_info_t *obj, unsigned int val)
| Set subdevice part of CTL element identifier of a CTL element id/info.
void | snd_ctl_elem_info_set_name (snd_ctl_elem_info_t *obj, const char *val)
| Set name part of CTL element identifier of a CTL element id/info.
void | snd_ctl_elem_info_set_index (snd_ctl_elem_info_t *obj, unsigned int val)
| Set index part of CTL element identifier of a CTL element id/info.
void | snd_ctl_elem_info_set_read_write (snd_ctl_elem_info_t *obj, int rval, int wval)
| Set readability/writeability parameter of a CTL element id/info.
void | snd_ctl_elem_info_set_tlv_read_write (snd_ctl_elem_info_t *obj, int rval, int wval)
| Set TLV readability/writeability parameter of a CTL element id/info.
void | snd_ctl_elem_info_set_inactive (snd_ctl_elem_info_t *obj, int val)
| Set inactive parameter of a CTL element id/info.
int | snd_ctl_add_integer_elem_set (snd_ctl_t *ctl, snd_ctl_elem_info_t *info, unsigned int element_count, unsigned int member_count, long min, long max, long step)
| Create and add some user-defined control elements of integer type.
int | snd_ctl_add_integer64_elem_set (snd_ctl_t *ctl, snd_ctl_elem_info_t *info, unsigned int element_count, unsigned int member_count, long long min, long long max, long long step)
| Create and add some user-defined control elements of integer64 type.
int | snd_ctl_add_boolean_elem_set (snd_ctl_t *ctl, snd_ctl_elem_info_t *info, unsigned int element_count, unsigned int member_count)
| Create and add some user-defined control elements of boolean type.
int | snd_ctl_add_enumerated_elem_set (snd_ctl_t *ctl, snd_ctl_elem_info_t *info, unsigned int element_count, unsigned int member_count, unsigned int items, const char *const labels[])
| Create and add some user-defined control elements of enumerated type.
int | snd_ctl_add_bytes_elem_set (snd_ctl_t *ctl, snd_ctl_elem_info_t *info, unsigned int element_count, unsigned int member_count)
| Create and add some user-defined control elements of bytes type.
int | snd_ctl_elem_add_integer (snd_ctl_t *ctl, const snd_ctl_elem_id_t *id, unsigned int count, long imin, long imax, long istep)
| Create and add an user-defined control element of integer type.
int | snd_ctl_elem_add_integer64 (snd_ctl_t *ctl, const snd_ctl_elem_id_t *id, unsigned int count, long long imin, long long imax, long long istep)
| Create and add an user-defined control element of integer64 type.
int | snd_ctl_elem_add_boolean (snd_ctl_t *ctl, const snd_ctl_elem_id_t *id, unsigned int count)
| Create and add an user-defined control element of boolean type.
int | snd_ctl_elem_add_enumerated (snd_ctl_t *ctl, const snd_ctl_elem_id_t *id, unsigned int count, unsigned int items, const char *const names[])
| Create and add a user-defined control element of enumerated type.
int | snd_ctl_elem_add_iec958 (snd_ctl_t *ctl, const snd_ctl_elem_id_t *id)
| Create and add a user-defined control element of IEC958 type.
int | snd_ctl_elem_remove (snd_ctl_t *ctl, snd_ctl_elem_id_t *id)
| Remove an user CTL element.
size_t | snd_ctl_elem_value_sizeof (void)
| Get size of data structure for an element.
int | snd_ctl_elem_value_malloc (snd_ctl_elem_value_t **ptr)
| Allocate an invalid snd_ctl_elem_value_t on the heap.
void | snd_ctl_elem_value_free (snd_ctl_elem_value_t *obj)
| Free an snd_ctl_elem_value_t previously allocated using snd_ctl_elem_value_malloc().
void | snd_ctl_elem_value_clear (snd_ctl_elem_value_t *obj)
| Clear given data of an element.
void | snd_ctl_elem_value_copy (snd_ctl_elem_value_t *dst, const snd_ctl_elem_value_t *src)
| Bitwise copy of a snd_ctl_elem_value_t value.
int | snd_ctl_elem_value_compare (snd_ctl_elem_value_t *left, const snd_ctl_elem_value_t *right)
| Compare two snd_ctl_elem_value_t values, bytewise.
void | snd_ctl_elem_value_get_id (const snd_ctl_elem_value_t *obj, snd_ctl_elem_id_t *ptr)
| Get the element identifier from the given element value.
unsigned int | snd_ctl_elem_value_get_numid (const snd_ctl_elem_value_t *obj)
| Get the identifiers 'numid' part from the given element value.
snd_ctl_elem_iface_t | snd_ctl_elem_value_get_interface (const snd_ctl_elem_value_t *obj)
| Get the identifiers 'interface' part from the given element value.
unsigned int | snd_ctl_elem_value_get_device (const snd_ctl_elem_value_t *obj)
| Get the identifiers 'device' part from the given element value.
unsigned int | snd_ctl_elem_value_get_subdevice (const snd_ctl_elem_value_t *obj)
| Get the identifiers 'subdevice' part from the given element value.
const char * | snd_ctl_elem_value_get_name (const snd_ctl_elem_value_t *obj)
| Get the identifiers 'name' part from the given element value.
unsigned int | snd_ctl_elem_value_get_index (const snd_ctl_elem_value_t *obj)
| Get the identifiers 'index' part from the given element value.
void | snd_ctl_elem_value_set_id (snd_ctl_elem_value_t *obj, const snd_ctl_elem_id_t *ptr)
| Set the element identifier within the given element value.
void | snd_ctl_elem_value_set_numid (snd_ctl_elem_value_t *obj, unsigned int val)
| Set the identifiers 'numid' part within the given element value.
void | snd_ctl_elem_value_set_interface (snd_ctl_elem_value_t *obj, snd_ctl_elem_iface_t val)
| Set the identifiers 'interface' part within the given element value.
void | snd_ctl_elem_value_set_device (snd_ctl_elem_value_t *obj, unsigned int val)
| Set the identifiers 'device' part within the given element value.
void | snd_ctl_elem_value_set_subdevice (snd_ctl_elem_value_t *obj, unsigned int val)
| Set the identifiers 'subdevice' part within the given element value.
void | snd_ctl_elem_value_set_name (snd_ctl_elem_value_t *obj, const char *val)
| Set the identifiers 'name' part within the given element value.
void | snd_ctl_elem_value_set_index (snd_ctl_elem_value_t *obj, unsigned int val)
| Set the identifiers 'index' part within the given element value.
int | snd_ctl_elem_value_get_boolean (const snd_ctl_elem_value_t *obj, unsigned int idx)
| Get an element members value.
long | snd_ctl_elem_value_get_integer (const snd_ctl_elem_value_t *obj, unsigned int idx)
| Get an element members value.
long long | snd_ctl_elem_value_get_integer64 (const snd_ctl_elem_value_t *obj, unsigned int idx)
| Get an element members value.
unsigned int | snd_ctl_elem_value_get_enumerated (const snd_ctl_elem_value_t *obj, unsigned int idx)
| Get an element members value.
unsigned char | snd_ctl_elem_value_get_byte (const snd_ctl_elem_value_t *obj, unsigned int idx)
| Get an element members value.
void | snd_ctl_elem_value_set_boolean (snd_ctl_elem_value_t *obj, unsigned int idx, long val)
| Set an element members value.
void | snd_ctl_elem_value_set_integer (snd_ctl_elem_value_t *obj, unsigned int idx, long val)
| Set an element members value.
void | snd_ctl_elem_value_set_integer64 (snd_ctl_elem_value_t *obj, unsigned int idx, long long val)
| Set an element members value.
void | snd_ctl_elem_value_set_enumerated (snd_ctl_elem_value_t *obj, unsigned int idx, unsigned int val)
| Set an element members value.
void | snd_ctl_elem_value_set_byte (snd_ctl_elem_value_t *obj, unsigned int idx, unsigned char val)
| Set an element members value.
void | snd_ctl_elem_set_bytes (snd_ctl_elem_value_t *obj, void *data, size_t size)
| Replace the data stored within the element.
const void * | snd_ctl_elem_value_get_bytes (const snd_ctl_elem_value_t *obj)
| Get the data stored within the element.
void | snd_ctl_elem_value_get_iec958 (const snd_ctl_elem_value_t *obj, snd_aes_iec958_t *ptr)
| Get an elements IEC958 data.
void | snd_ctl_elem_value_set_iec958 (snd_ctl_elem_value_t *obj, const snd_aes_iec958_t *ptr)
| Set an elements IEC958 data.
int | snd_tlv_parse_dB_info (unsigned int *tlv, unsigned int tlv_size, unsigned int **db_tlvp)
| Parse TLV stream and retrieve dB information.
int | snd_tlv_get_dB_range (unsigned int *tlv, long rangemin, long rangemax, long *min, long *max)
| Get the dB min/max values.
int | snd_tlv_convert_to_dB (unsigned int *tlv, long rangemin, long rangemax, long volume, long *db_gain)
| Convert the given raw volume value to a dB gain.
int | snd_tlv_convert_from_dB (unsigned int *tlv, long rangemin, long rangemax, long db_gain, long *value, int xdir)
| Convert from dB gain to the corresponding raw value.
int | snd_ctl_get_dB_range (snd_ctl_t *ctl, const snd_ctl_elem_id_t *id, long *min, long *max)
| Get the dB min/max values on the given control element.
int | snd_ctl_convert_to_dB (snd_ctl_t *ctl, const snd_ctl_elem_id_t *id, long volume, long *db_gain)
| Convert the volume value to dB on the given control element.
int | snd_ctl_convert_from_dB (snd_ctl_t *ctl, const snd_ctl_elem_id_t *id, long db_gain, long *value, int xdir)
| Convert from dB gain to the raw volume value on the given control element.
int | snd_hctl_compare_fast (const snd_hctl_elem_t *c1, const snd_hctl_elem_t *c2)
| A "don't care" fast compare functions that may be used with snd_hctl_set_compare.
int | snd_hctl_open (snd_hctl_t **hctl, const char *name, int mode)
| Opens an HCTL.
int | snd_hctl_open_ctl (snd_hctl_t **hctlp, snd_ctl_t *ctl)
| Opens an HCTL.
int | snd_hctl_close (snd_hctl_t *hctl)
| close HCTL handle
int | snd_hctl_nonblock (snd_hctl_t *hctl, int nonblock)
| set nonblock mode
int | snd_hctl_poll_descriptors_count (snd_hctl_t *hctl)
| get count of poll descriptors for HCTL handle
int | snd_hctl_poll_descriptors (snd_hctl_t *hctl, struct pollfd *pfds, unsigned int space)
| get poll descriptors
int | snd_hctl_poll_descriptors_revents (snd_hctl_t *ctl, struct pollfd *pfds, unsigned int nfds, unsigned short *revents)
| get returned events from poll descriptors
unsigned int | snd_hctl_get_count (snd_hctl_t *hctl)
| Get number of loaded elements for an HCTL.
int | snd_hctl_set_compare (snd_hctl_t *hctl, snd_hctl_compare_t hsort)
| Change HCTL compare function and reorder elements.
snd_hctl_elem_t * | snd_hctl_first_elem (snd_hctl_t *hctl)
| get first element for an HCTL
snd_hctl_elem_t * | snd_hctl_last_elem (snd_hctl_t *hctl)
| get last element for an HCTL
snd_hctl_elem_t * | snd_hctl_find_elem (snd_hctl_t *hctl, const snd_ctl_elem_id_t *id)
| Search an HCTL element.
void | snd_hctl_set_callback (snd_hctl_t *hctl, snd_hctl_callback_t callback)
| Set callback function for an HCTL.
void | snd_hctl_set_callback_private (snd_hctl_t *hctl, void *data)
| Set callback private value for an HCTL.
void * | snd_hctl_get_callback_private (snd_hctl_t *hctl)
| Get callback private value for an HCTL.
int | snd_hctl_load (snd_hctl_t *hctl)
| Load an HCTL with all elements and sort them.
int | snd_hctl_free (snd_hctl_t *hctl)
| free HCTL loaded elements
int | snd_hctl_handle_events (snd_hctl_t *hctl)
| Handle pending HCTL events invoking callbacks.
const char * | snd_hctl_name (snd_hctl_t *hctl)
| get identifier of HCTL handle
int | snd_hctl_wait (snd_hctl_t *hctl, int timeout)
| Wait for a HCTL to become ready (i.e. at least one event pending)
snd_ctl_t * | snd_hctl_ctl (snd_hctl_t *hctl)
| Get a ctl handle associated to the given hctl handle.
snd_hctl_elem_t * | snd_hctl_elem_next (snd_hctl_elem_t *elem)
| get next HCTL element
snd_hctl_elem_t * | snd_hctl_elem_prev (snd_hctl_elem_t *elem)
| get previous HCTL element
int | snd_hctl_elem_info (snd_hctl_elem_t *elem, snd_ctl_elem_info_t *info)
| Get information for an HCTL element.
int | snd_hctl_elem_read (snd_hctl_elem_t *elem, snd_ctl_elem_value_t *value)
| Get value for an HCTL element.
int | snd_hctl_elem_write (snd_hctl_elem_t *elem, snd_ctl_elem_value_t *value)
| Set value for an HCTL element.
int | snd_hctl_elem_tlv_read (snd_hctl_elem_t *elem, unsigned int *tlv, unsigned int tlv_size)
| Get TLV value for an HCTL element.
int | snd_hctl_elem_tlv_write (snd_hctl_elem_t *elem, const unsigned int *tlv)
| Set TLV value for an HCTL element.
int | snd_hctl_elem_tlv_command (snd_hctl_elem_t *elem, const unsigned int *tlv)
| Set TLV value for an HCTL element.
snd_hctl_t * | snd_hctl_elem_get_hctl (snd_hctl_elem_t *elem)
| Get HCTL handle for an HCTL element.
void | snd_hctl_elem_get_id (const snd_hctl_elem_t *obj, snd_ctl_elem_id_t *ptr)
| Get CTL element identifier of a CTL element id/value.
unsigned int | snd_hctl_elem_get_numid (const snd_hctl_elem_t *obj)
| Get element numeric identifier of a CTL element id/value.
snd_ctl_elem_iface_t | snd_hctl_elem_get_interface (const snd_hctl_elem_t *obj)
| Get interface part of CTL element identifier of a CTL element id/value.
unsigned int | snd_hctl_elem_get_device (const snd_hctl_elem_t *obj)
| Get device part of CTL element identifier of a CTL element id/value.
unsigned int | snd_hctl_elem_get_subdevice (const snd_hctl_elem_t *obj)
| Get subdevice part of CTL element identifier of a CTL element id/value.
const char * | snd_hctl_elem_get_name (const snd_hctl_elem_t *obj)
| Get name part of CTL element identifier of a CTL element id/value.
unsigned int | snd_hctl_elem_get_index (const snd_hctl_elem_t *obj)
| Get index part of CTL element identifier of a CTL element id/value.
void | snd_hctl_elem_set_callback (snd_hctl_elem_t *obj, snd_hctl_elem_callback_t val)
| Set callback function for an HCTL element.
void * | snd_hctl_elem_get_callback_private (const snd_hctl_elem_t *obj)
| Get callback private value for an HCTL element.
void | snd_hctl_elem_set_callback_private (snd_hctl_elem_t *obj, void *val)
| Set callback private value for an HCTL element.
int | snd_sctl_build (snd_sctl_t **ctl, snd_ctl_t *handle, snd_config_t *config, snd_config_t *private_data, int mode)
| Build setup control handle.
int | snd_sctl_free (snd_sctl_t *handle)
| Free setup control handle.
int | snd_sctl_install (snd_sctl_t *handle)
| Install given values to control elements.
int | snd_sctl_remove (snd_sctl_t *handle)
| Remove (restore) previous values from control elements.
int | snd_device_name_hint (int card, const char *iface, void ***hints)
| Get a set of device name hints.
int | snd_device_name_free_hint (void **hints)
| Free a list of device name hints.
char * | snd_device_name_get_hint (const void *hint, const char *id)
| Extract a value from a hint.

## Detailed Description

Application interface library for the ALSA driver.

Author
  Jaroslav Kysela perex.nosp@m.@per.nosp@m.ex.cz
  Abramo Bagnara abram.nosp@m.o@al.nosp@m.sa-pr.nosp@m.ojec.nosp@m.t.org
  Takashi Iwai tiwai.nosp@m.@sus.nosp@m.e.de

Date
  1998-2001

Application interface library for the ALSA driver

## Macro Definition Documentation

## ◆ __ALSA_CONTROL_H

#define __ALSA_CONTROL_H

header include loop protection